The Disordered Mind: What Unusual Brains Tell Us About Ourselves

by Eric R. Kandel

Another person who challenged the idea that a complex neural circuit is required for learning was the Canadian psychologist Donald Hebb. Hebb suggested that associative learning could be produced by the simple interaction of two neurons: if neuron A repeatedly stimulates neuron B to fire an action potential—the electrical impulse that travels down the axon to the synapse—a change will take place in one or both of those cells. That change strengthens the synaptic connection between the two neurons. The strengthened connection creates and stores, for a short time, a memory of the interaction.3 Two researchers working at the University of Göteborg in Sweden, Holger Wigström and Bengt Gustafsson, later provided the first evidence suggesting that Hebb’s mechanism might be at work in the formation of explicit memory in the hippocampus.